1. Field
Some example embodiments relate to a position arrangement device having improved positioning accuracy.
2. Description of the Related Art
In general, kinematic joints are used to assure arrangement of high-precision parts at accurate positions during assembly or disassembly thereof. Although kinematic joints are designed based on various principles, point contact between a ball and a plane is generally employed. Under the concept that contact between a ball and a plane has one degree of freedom, point contact between three balls and six planes will have six degrees of freedom x, y, z, θ x, θ y and θ z, which enables positioning with accuracy and repeatability. Arranging three balls and corresponding planes may include the following two representative examples. In the first example, “3-2-1” point contacts are obtained using the combination of a tetrahedron, a V-shaped groove and a plane, whereby a total of six point contacts have six degrees of freedom. In the second example, three V-shaped planes are radially arranged by 120 degrees (or other corresponding angles), whereby a total of six point contacts have six degrees of freedom.
The above-described kinematic joints have characteristics of being fixed at accurate positions even if they are repeatedly assembled and disassembled and therefore, are employed in a variety of high-precision equipment including high-precision optical systems. However, since using the kinematic joints may often require control of the posture of a corresponding plane, a device to transfer one side of the kinematic joint in a height direction may be necessary. To this end, various joint transfer devices may be put to use.